We forget our infancy as we start to think like adults.

Why can’t we remember our early life? It is a question I am frequently asked. The conventional answer is that our experience as a baby and toddler was so different that it is very difficult to retrieve those memories. And even if we could remember the memories themselves wouldn’t make much sense to us.

New research from Emory University seems to support this. Childhood amnesia seems to start from around the age of 7 and it seems to be related to the onset of more adult-like memory patterns. Christian Jarrett at the BPS blog explains this nicely:

Patricia Bauer and Marina Larkina … recorded mothers talking to their 3-year-olds about six past events, such as zoo visits or first day at pre-school. The researchers then re-established contact with the same families at different points in the future. Some of the children were quizzed again by a researcher when aged 5, others at age 6 or 7, 8 or 9. This way the researchers were able to chart differences in amounts of forgetting through childhood.

Bauer and Larkina uncovered a paradox – at ages 5 to 7, the children remembered over 60 per cent of the events they’d chatted about at age 3. [T]heir recall for these events was immature… In contrast, children aged 8 and 9 recalled fewer than 40 per cent of the events…, but those memories they did recall were more adult-like,

The researchers also suggest that the mere act of remembering toddlerhood when aged 5-7 in this immature way may contribute subsequent amnesia through a process called “retrieval-induced forgetting“. In adult experiments this is demonstrated where strong recall of one item on a list makes it much hard to recall related items learned at the same time. An experience we’ve all had in exams when our minds go blank. For children focusing on an event they do remember may effectively wipe many related memories. Certainly, anecdotal evidence suggests that if we do have memories of early childhood we usually only have one or two.